This is an imaging study of the major psychoses, principally schizophrenia, using two imaging modalities: MR and PET. The studies involve anatomical and physiological mapping of the brain in normal individuals and in patients suffering from schizophrenia. The MR studies emphasize the ongoing development of methods for image analysis that involve three dimensional visualization using surface/volume rendering. These studies will emphasize the measurement of sulcal and gyral patterns, as well as methods for measuring surface and internal brain structures and documenting the reliability and validity of such measurements. The MR studies will examine sulcal and gyral patterns in normal individuals in relation to gender, intelligence, and specialized cognitive abilities. Because sulcal patterns reflect major neurodevelopmental events, these techniques will also be applied to the study of schizophrenia, since such approaches may shed light on the timing or nature of neurodevelopmental abnormalities in schizophrenia. The PET studies will use an 15O water paradigm. In these studies, as in MR studies, the first steps will be the evaluation of normal individuals, followed by the study of patients with schizophrenia after the methodology has been thoroughly worked out. The PET studies will emphasize three cognitive systems of interest to schizophrenia: language, attention, and memory.